This can be a pretty useful card depending on what's going on in combat phase. Let's just say you just had a slew of creatures become a target of opponent spells- you counter, they recounter, and now you're out of spells, pop Snapcaster Mage onto the 'field and those spells you just used, can be flashed back dependent on if you have the mana (as this ability only lasts till the end of turn).